Ethernet is used in various systems to transfer frames via intermediary devices (e.g., switches, bridges, routers, etc.) between endpoint devices. For example, there is an emerging use for Ethernet as a mechanism to transfer various data to automotive systems. One or more of the intermediary devices and/or endpoint devices (both of which are referred to herein as network devices) typically have a processor. The processor executes firmware to perform predetermined tasks. In order to test the processor and/or debug errors in the firmware during development, manufacturing and/or use of the processor, a host device is connected via a joint test action group (JTAG) port or a serial wire port on the corresponding network device. If the network device is located within a vehicle, the host device accesses the JTAG port or the serial wire port of the network device via a vehicle interface (sometimes referred to as a diagnostic connector). The host device executes a test and/or debug process through transfer of signals via the JTAG port or serial wire port to test and/or debug the processor.
In an automotive vehicle, it is difficult to access network devices to be tested and/or debugged. For example, certain network devices are located in a vehicle, such that there is restricted physical access to the network devices. In addition and/or alternatively some network devices are incorporated in molded housings (e.g., housings of sensors, such as cameras, where the housings are formed of plastic) for protection purposes, thereby preventing physical access to the network devices. The housings protect the network devices from, for example, environmental elements and prevent the network devices from coming in contact with water.
To prevent intruders from accessing the stated processors, a network device can be manufactured without a JTAG port or a serial wire port. This aids in preventing an intruder from gaining access to the processors and/or a corresponding network (e.g., an internal automotive network of a vehicle) by connecting a standard debugging device to a diagnostic connector of the vehicle.